Fair Value (Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	$ 391,772	$ 146,466
Investment securities	1,502,552	1,514,811
Federal Home Loan Bank Stock	50,086	50,086
Federal Reserve Bank Stock	8,225	8,225
Loans Held-for-sale, Fair Value Disclosure	6,722	10,413
Impaired Loan Fair Value	4,319	5,983
Other loans	5,185,883	5,161,919
Loans receivable, net	5,197,158	5,178,439
Noninterest bearing checking accounts	1,548,363	1,523,417
Interest bearing transactions accounts	1,310,575	1,174,448
Savings accounts	1,928,507	1,704,920
Time deposits	1,133,360	1,122,598
Other	2,706	1,301
Total deposits	5,923,511	5,526,684
Short-term borrowings	219,863	394,795
Long-term debt	760,798	712,958
Subordinated debentures/notes	43,786	40,903
Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226	226
Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	4,179	3,849
Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	14,449	14,973
Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	901	900
Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,288	1,251
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	391,772	146,466
Investment securities	1,503,857	1,517,972
Loans Held-for-sale, Fair Value Disclosure	6,722	10,413
Derivative Assets	234	124
Impaired Loan Fair Value	4,319	5,983
Other loans	5,252,444	5,204,713
Loans receivable, net	5,263,719	5,221,233
Noninterest bearing checking accounts	1,548,363	1,523,417
Interest bearing transactions accounts	1,310,575	1,174,448
Savings accounts	1,928,507	1,704,920
Time deposits	1,130,409	1,117,870
Other	2,706	1,301
Total deposits	5,920,560	5,521,956
Short-term borrowings	219,863	394,795
Long-term debt	745,840	694,281
Subordinated debentures/notes	45,000	45,000
Reported Value Measurement [Member] | Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226	226
Reported Value Measurement [Member] | Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	4,179	3,849
Reported Value Measurement [Member] | Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	14,449	14,973
Reported Value Measurement [Member] | Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	901	900
Reported Value Measurement [Member] | Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,288	1,251
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	$ 234	124
Impaired Loan Fair Value		$ 5,983